PTGS2 and neoplasm: Consistently, PROS reduced the expression of p-Src, p-AKT, cyclooxygenase 2 (COX-2) as survival genes and suppressor of cytokine signaling 1 (SOCS-1) that promotes tumor progression and toll like receptor (TLR) signaling [40] , but not SHP-1, in A549 and H460 cells (Figure 3D).